Stephan nachtigal



STATES STEPHAN NAOHTIGAL,

tric.

OF DETROIT, MICHIGAN, ASSIGNOR TO ANTON LANGE, OF SAME PLACE.

CHUCK.

SPECIFICATION forming part of Letters Patent No. 538,082, dated April23, 1895. Application led January 21,1895. Serial No. 535,622. (Nomodel.)

To all whom it may concern:

Be it know-n that I, STEPHAN NACHTIGAL,

'a citizen of Germany, residing at Detroit,

county of Wayne, State of Michigan, have invented a certain new anduseful Improvement in Chucks; and I declare the following to be a full,clear, and exact description of the invention, such as will enableothers skilled in the art to which it pertains to make and use the same,reference being had to the accompanying drawings, which form a part ofthis specification.

This invention relates to chucks, and has for its object an improvementin that class of chucks which are especially intended to be used for thepurpose of holding the buttons or other similar small flat round disksto be treated by a cutting tool.

In the drawings, Figure 1 shows in section the chuck, with one jaw shownin position. Fig. 2 is an end elevation of the chuck. Fig. 3 is aperspective on alarge scale of the chuck frame with the jaws removed.Fig. 4 shows the jaw actuator on an enlarged scale. Fig. 5 shows a partof the jaw.

The chuck consists of a head A, to which is connected the stem a, bymeans of which it is held in bearin gs, or in any suitable rotatingdevice. The head is provided with three or more radial slots, 1, 2, and3, and in each of these slots is held a jaw piece 4. The jaw pieceisheld in piace in the slot by a pin 5 which passes through the jawpiece 4 and projects at either side in the form of a trunnion, theprojecting part of the pin engaging within the holes 6 and 7in the wallsat either side of the slot 1, the other jaws being held in a preciselysimilar way, each in its own slot. At the forward end of each jaw 4 is aplate, and of these plates there are as many as there are slots. Asshown in the drawings, there are three of them, each one occupying abouta third `of the area of the circle which forms the end of the head A..The central part of the face formed by these three pieces is cut out toreceive the disk to be treated, the walls of the central hole beingformed with a step or ledge 12 on which the disk to be treated restswhile it is gripped and held in place by that portion of the wall whichrises parallel with the axis of the chuck and beyond the ledge.

Each one of the pieces 9, 10 and 11 is held to the hinge piece to whichit belongs (to the piece 4, or the pieces similar toit) by a screw 13.At the inner side of each of the pieces 4 is a groove into which isreceived the flange 14 on the end of an actuator 15. The actuator isheld by a key 16, that passes through the opening 16a, and straddles therod between the two collars 17a 17h, one of which, 17a, is secured tothe rod, and the other, 17h, being loose thereon. The rod 17 isconcentric with and located within the tubular stem a of the chuck. Atone part the rod 17 is reduced in diameter, and around the reduced partis a spiral spring 18, so arranged as to normally retract the rod 17 anddraw its forward end 19 back from the plane of the ledges 12; but it canbe forced by the operator against the tension of the spring forward adistance sufcient to force the disk or button out from the jaws whichare rst spread slightly by the engagement between the flange 14 and theedge of the groove in the piece 4. By pushing the actuator 15 and therod forward, the jaws are slightly opened and the button or disk isexpelled.

To place the button or disk in position to be held, the jaws areslightly spread by pushing the actuator upward, not enough, however, tocause the end 19 to rise to the plane of the ledges 12. The button ordisk is then placed in position, and the rod or actuator, retracted bythe spring 18, engages with the groove on the opposite side, and rockingthe jaws around the pins 5, contracts the jaws slightly and grasps thebutton firmly. Y

Vhat I claim as novel is- 1. A disk holding chuck, comprising a holdinghead, rocking jaws pivoted in said head at one end and having their freeends grooved, a jaw actuator having a liange formed thereon Aadapted toengage with said grooves, means secured to said rocking jaws ywherebysaid disks are held, means for operating said jaw actuator, and anexpelling rod adapted to expel the disk after said jaws have beenexpanded, substantially as described.

2. In a disk holding chuck, the combination of a holding head havingradial slots formed therein and a tubular stem formed integraltherewith, rocking jaws pivoted at one end in Y engaged within saidholding head, adapted to actuate said jaws in both directions, a rodadapted to operate said actuator, and means engaging with said rod andactuator whereby said rod is allowed to move for a limited spaceindependent of said actuator, substantially as described.

In testimony whereof I sign this specification in the presence of twowitnesses.

STEPHAN NACHTIGAL. Witnesses:

J. M. GLoUGH, C. F. BURTON.

